With the rapid growing of microblog, the need to discover the trending topics in microblogs becomes more and more pressing. Although topic detection has long been a hotspot research, it is difficult to discover the trending topics with high contextual meaning because the microblogs are small elements of content, such as short sentences, individual images, or video links. This paper proposes a n...

Phishing attacks are one of the trending cyber-attacks that apply socially engineered messages that are communicated to people from professional hackers aiming at fooling users to reveal their sensitive information, the most popular communication channel to those messages is through users’ emails. This paper presents an intelligent classification model for detecting phishing emails using knowle...

Online trending topics represent the most popular topics among users in certain online community, such as a country community. Trending topics in one community are different from others since the users in the community may discuss different topics from other communities. Surprisingly, almost 90% of trending topics are diffused among multiple online communities, so it shows peoples interests in ...

In a market with one safe and one risky asset, an investor with a long horizon, constant investment opportunities, and constant relative risk aversion trades with small proportional transaction costs. We derive explicit formulas for the optimal investment policy, its implied welfare, liquidity premium, and trading volume. At the first order, the liquidity premium equals the spread, times share ...

Rotaviruses are the major etiological agents of diarrhea in children less than 5 years of age. The commonest G types in humans are G1-4 and G9. G12 is a rare human rotavirus (HRV) strain first reported in the Philippines. In this study, 13 G12 strains obtained from a community-based cohort and a hospital-based surveillance system in 2005 were characterized by phylogenetic analysis of partial nu...

Did the unification of commercial and investment banking heighten risk in financial markets due to moral hazard of borrowers? In a simple intertemporal model with moral hazard and uninsured risk, we argue that if financial contracts are properly written, the integration in financial markets could give rise to greater risk sharing arrangement and could eliminate the equity risk premium attribute...

I develop an asset-pricing model in which financial assets are valued for their liquidity– the extent to which they are useful in facilitating exchange–as well as for being claims to streams of consumption goods. The implications for average asset returns, the equitypremium puzzle, and the risk-free rate puzzle, are explored both analytically and quantitatively in a version of the model that ne...

We examine the relation between trading volume and skewness in 11 international stock markets using daily and monthly data from January 1980 to August 2004. We construct single equation and VAR models of the relation between the first three moments of market returns and trading volumes. Our results show hitherto unrecognised channels of influence, and support the investor heterogeneity approach...

Assuming elliptically contoured distribution for portfolio asset returns, we derive the exact marginal and joint densities of the global minimum variance portfolio variance, and weights estimators. We also construct a test for the hypothesis that the global minimum variance is less then or equal to a certain value. A stochastic representation and moments of its estimator is provided. We illustr...